package com.atguigu.gulimall.product.service.impl;

import com.atguigu.gulimall.product.dao.BrandDao;
import com.atguigu.gulimall.product.entity.CategoryBrandRelationEntity;
import com.atguigu.gulimall.product.service.CategoryBrandRelationService;
import org.checkerframework.checker.units.qual.A;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.*;
import java.util.stream.Collectors;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.atguigu.common.utils.PageUtils;
import com.atguigu.common.utils.Query;

import com.atguigu.gulimall.product.dao.CategoryDao;
import com.atguigu.gulimall.product.entity.CategoryEntity;
import com.atguigu.gulimall.product.service.CategoryService;
import org.springframework.transaction.annotation.Transactional;


@Service("categoryService")
public class CategoryServiceImpl extends ServiceImpl<CategoryDao, CategoryEntity> implements CategoryService {

    @Autowired
    CategoryDao categoryDao;

    @Autowired
    CategoryBrandRelationService categoryBrandRelationService;


    @Override
    public PageUtils queryPage(Map<String, Object> params) {
        IPage<CategoryEntity> page = this.page(
                new Query<CategoryEntity>().getPage(params),
                new QueryWrapper<CategoryEntity>()
        );

        return new PageUtils(page);
    }

    @Override
    public List<CategoryEntity> listWithTree() {
        //查出所有分类
        List<CategoryEntity> entities = baseMapper.selectList(null);

        //组装父子结构

        //找到所有一级分类
        List<CategoryEntity> level1Menus = entities.stream().filter(categoryEntity ->
                categoryEntity.getParentCid() == 0
        ).map((menu)->{
            menu.setChildren(getChildren(menu,entities));
            return menu;
        }).sorted((menu1,menu2)->{
            return (menu1.getSort()==null?0:menu1.getSort()) - (menu2.getSort()==null?0:menu2.getSort());
        }).collect(Collectors.toList());

        return level1Menus;
    }

    /**
     *
     * @param asList
     */
    @Override
    public void removeMenuByIds(List<Long> asList) {
        //TODO 检查当前删除菜单是否被引用
        baseMapper.deleteBatchIds(asList);
    }

    /**
     * 找到catelogId完整路径
     * [父/子/孙]
     * @param catelogId
     * @return
     */
    @Override
    public Long[] findCatelogPath(Long catelogId) {
        //收集当前节点id
        List<Long> paths = new ArrayList<>();
        List<Long> parentPath = findParentPath(catelogId, paths);

        //将集合里数据反序列化
        Collections.reverse(parentPath);

        return (Long[]) parentPath.toArray(new Long[parentPath.size()]);
    }

    /**
     * 级联更新
     * @param category
     */
    @Transactional //开启事务
    @Override
    public void updateCascade(CategoryEntity category) {
        this.updateById(category);
        categoryBrandRelationService.updateCascade(category.getCatId(),category.getName());

    }

    private List<Long> findParentPath(Long catelogId , List<Long> paths ){
        paths.add(catelogId);
        CategoryEntity byId = this.getById(catelogId);
        if (byId.getParentCid()!=0){
            findParentPath(byId.getParentCid(),paths);
        }
        return paths;
    }


    /**
     * 递归查找所有菜单的子菜单
     * @param root
     * @param all
     * @return
     */
    private  List<CategoryEntity> getChildren(CategoryEntity root, List<CategoryEntity> all){
        List<CategoryEntity> collect = all.stream().filter(categoryEntity -> {
            return categoryEntity.getParentCid().equals(root.getCatId());
        }).map(categoryEntity -> {
            categoryEntity.setChildren(getChildren(categoryEntity, all));
            return categoryEntity;
        }).sorted((menu1, menu2) -> {
            return (menu1.getSort()==null?0:menu1.getSort()) - (menu2.getSort()==null?0:menu2.getSort());
        }).collect(Collectors.toList());
        return collect;
    }
}